The goal of this program is to continue to provide broad based interdisciplinary cancer research training for five predoctoral and five postdoctoral fellows. Trainees funded by this program will work with two faculty members whose complementary research interests lie in basic sciences, clinical research or public health sciences. In order to obtain funding through this training grant, fellows must submit research proposals relevant to the etiology or treatment of cancer that draw upon expertise found in two or more disciplines and identify two mentors who agree to supervise the project. This training program is the centerpiece of an overall initiative in interdisciplinary cancer research at the Fred Hutchinson Cancer Research Center (FHCRC) and the University of Washington (UW). The long-term goal is to increase the pool of investigators who have training and expertise in cross-disciplinary applications of the rapidly expanding knowledge base in biomedical science relevant to cancer and other human diseases. Examples of such cross disciplinary training are basic science students who have two advisors who are a basic scientist and an epidemiologist, or clinical fellows who also have a basic science or a public health science advisor for portions of the work. The research experience will be supported by selection from a wide range of didactic training opportunities appropriate to the needs of the individual trainee and available at the two institutions, including research meetings, classes, journal clubs and seminars. All trainees will present their work annually at a research colloquium. An additional component of this program is support of predoctoral students who wish to obtain an M.S. degree in Epidemiology, concurrent with a Ph.D. in a basic science. A concurrent Dual Degree program has been established at the University of Washington to allow this type of interdisciplinary training in an efficient manner. Trainees will be recruited from the pool of predoctoral and postdoctoral trainees presently working at the two institutions. In addition, trainees can learn about specific interdisciplinary research opportunities through a web site devoted to dual mentor projects. This web site, and the projects therein, will be advertised locally and nationally, so that postdoctoral trainees from other institutions can also apply to the program.